A50.40 – Late congenital neurosyphilis, unspecified

ICD-10-CM 2027 diagnosis code · Infections with a predominantly sexual mode of transmission

Billable code

ICD-10-CM code A50.40

Code: A50.40 (claims format: A5040)
Description: Late congenital neurosyphilis, unspecified
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 1. Certain infectious and parasitic diseases (A00-B99)
Block: A50-A64 Infections with a predominantly sexual mode of transmission
Parent codes: A50 › A50.4

Notes for A50.40

Applicable to:

Juvenile neurosyphilis NOS

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

A50.4 – Late congenital neurosyphilis [juvenile neurosyphilis]

Excludes1 (not coded here):

Hutchinson's triad (A50.53)

Use additional code:

code to identify any associated mental disorder

Block A50-A64

Excludes1 (not coded here):

nonspecific and nongonococcal urethritis (N34.1)
Reiter's disease (M02.3-)

Excludes2 (not included here):

human immunodeficiency virus [HIV] disease (B20)

Index terms for A50.40

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in A50.4

A50.41 – Late congenital syphilitic meningitisBillable
A50.42 – Late congenital syphilitic encephalitisBillable
A50.43 – Late congenital syphilitic polyneuropathyBillable
A50.44 – Late congenital syphilitic optic nerve atrophyBillable
A50.45 – Juvenile general paresisBillable
A50.49 – Other late congenital neurosyphilisBillable

Frequently asked questions

What is ICD-10 code A50.40?

A50.40 is the ICD-10-CM code for late congenital neurosyphilis, unspecified, in the block A50-A64 (Infections with a predominantly sexual mode of transmission).

Is A50.40 a billable code?

Yes. A50.40 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does A50.40 belong to?

It belongs to category A50 – Congenital syphilis.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.